This book examines the responsibility of States and international organizations for complicity (aid or assistance) in an internationally wrongful act. Despite the recognition of responsibility for complicity as a rule of customary international law by the International Court of Justice, this book argues that the effectiveness and utility of this form of responsibility is fraught with systemic and operational limits. These limits include a lack of clarity in its constituent elements, its co-existence with primary rules prohibiting complicity and the obligations of due diligence, its implementation and the underlying causal tests, its uncertain relationship to other forms of shared and indirect responsibility, and its potential as a form of attribution of conduct. This book submits that the content and elements of this form of responsibility need adjustments to respond more effectively to the phenomenon of complicity in international affairs. Awarded The Paul Guggenheim Prize in International Law 2017!

This systematic analysis of State complicity in international law focuses on the rules of State responsibility. Combining a theoretical perspective on complicity based on the concept of the international rule of law with a thorough analysis of international practice, Helmut Philipp Aust establishes what forms of support for wrongful conduct entail responsibility of complicit States and sheds light on the consequences of complicity in terms of reparation and implementation. Furthermore, he highlights how international law provides for varying degrees of responsibility in cases of complicity, depending on whether peremptory norms have been violated or special subject areas such as the law of collective security are involved. The book shows that the concept of State complicity is firmly grounded in international law, and that the international rule of law may serve as a conceptual paradigm for today's international legal order.

Complicity in International Law aims to analyze questions arising from a state's complicity in conflict with another state or an international organization. On the basis of international legal provisions, a state that assists the illicit fact of another state or an international organization in turn commits an offense if it is aware of the main fact and is bound by the same obligation.International law offers adumbrates the outcome of a codification process undertaken by the International Law Commission. The practice and its consequences, and the reflections of the doctrine, have matured with regard to the original hypothesis. Several cases of participation in the unlawful conduct of others, for example in facilitating the illicit use of the armed force, or of financial support to states responsible for human rights violations, have been recorded since the period immediately following World War II.International doctrine has long shown great interest in the theme of competition of several subjects in an international illicit act. This is a new phenomenon, given that until recently the issue had been the subject of in-depth analysis in a small number of works, few of which have been monographic in nature. Complicity in International Law will address the issue comprehensively.

This book examines how international law prohibits state and individual complicity. Complicity is a derivative form of responsibility that links an accomplice to the wrongdoing of a principal actor. Whenever a legal system prohibits complicity, it must address certain questions as to the content and structure of the rules. To understand how international law answers these questions, this book proposes an analytical framework in which complicity rules may be assessed and defends a normative claim as to how they should be structured. Anchored by this framework and normative claim, this book shows that international criminal law regulates individual complicity in a comprehensive way, using the doctrines of instigation and aiding and abetting to inculpate complicit participants in international crimes. By contrast, international law's regulation of state complicity was historically marked by an absence of complicity rules. This is changing. In respect of state complicity in the wrongdoing of another state, international law now imposes both specific and general complicity obligations, the latter prohibiting states from aiding or assisting another state in the commission of any internationally wrongful act. In respect of the ways that states participate in harms caused by non-state actors, the traditional normative structure of international law, which imposed obligations only on states, foreclosed the possibility of prohibiting the state's participation as a form of complicity. As that traditional normative structure has evolved, so the possibility of holding states responsible for complicity in the wrongdoing of non-state actors has emerged. More and more, both the wrongs that international actors commit, and the wrongs they help or encourage others to commit, matter.

The Shared Responsibility in International Law series examines the underexplored problem of allocation of responsibilities among multiple states and other actors. The International Law Commission, in its work on state responsibility and the responsibility of international organisations, recognised that attribution of acts to one state or organisation does not exclude possible attribution of the same act to another state or organisation, but has provided limited guidance on allocation or reparation. From the new perspective of shared responsibility, this volume reviews the main principles of the law of international responsibility as laid down in the Articles on State Responsibility and the Articles on Responsibility of International Organizations, such as attribution of conduct, breach, circumstances precluding wrongfulness and reparation. It explores the potential and limitations of current international law in dealing with questions of shared responsibility in areas such as military operations and international environmental law.

The law of international responsibility is one of international law's core foundational topics. Written by international experts, this book provides an overview of the modern law of international responsibility, both as it applies to states and to international organizations, with a focus on the ILC's work.

State responsibility in international law is considered one of the cornerstones of the field. For a long time it remained the exclusive responsibility system due to the primacy of States as subjects of international law. Its unique position has nonetheless been challenged by several developments both within and outside the international legal order, such as the rise of alternative responsibility ideas and practices, as well as globalization and its consequences. This book adopts a critical and holistic approach to the law of State responsibility and analyzes the functionality of the general rules of State responsibility in a changed international landscape characterized by the fragmentation of responsibility. It is argued that State responsibility is not equally relevant across the broad spectrum of international obligations, and that alternative constructions of responsibility, namely international criminal law and international liability, have increased in standing.